Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
J Am Chem Soc. 2021 Apr 7;143(13):4928-4934. doi: 10.1021/jacs.1c01556. Epub 2021 Mar 29.
Minisci-type reactions constitute one of the most powerful methods for building up complexity around basic heteroarenes. The most desirable variants involve formal oxidative coupling of a C-H bond on each partner, leading back to the simplest possible starting materials. We herein disclose a method that enables such a coupling of linear amides and heteroarenes with full control of enantioselectivity at the newly formed stereocenter as well as site selectivity on both the heteroarene and the amide. This is achieved by the use of a chiral phosphoric acid catalyst in conjunction with diacetyl as a combined hydrogen atom transfer reagent and oxidant. Diacetyl is directly photoexcitable, and thus, no extraneous photocatalyst is required: an added feature that contributes to the simplicity and practicality of the protocol.
米斯基型反应是构建基本杂芳环周围复杂性的最有力方法之一。最理想的变体涉及每个伙伴上 C-H 键的正式氧化偶联,从而回到最简单的起始材料。我们在此公开了一种方法,该方法能够使线性酰胺和杂芳烃进行这种偶联,并且可以完全控制新形成的立体中心的对映选择性以及杂芳烃和酰胺上的位点选择性。这是通过使用手性磷酸催化剂与二乙酰基一起作为氢原子转移试剂和氧化剂来实现的。二乙酰基可直接光激发,因此不需要额外的光催化剂:这一额外的特点有助于该方案的简单性和实用性。